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981.
Wet atmospheric samples were collected from different locations in the southern region of Jordan during a 5-year period (October 2006 to May 2011). All samples were analyzed for pH, EC, major ions (Ca2+, Mg2+, Na+, K+, HCO3 ?, Cl?, NO3 ?, and SO4 2?), and trace metals (Fe2+, Al3+,Cu2+, Pb2+, and Zn2+). The highest ion concentrations were observed during the beginning of the rainfall events because large amounts of dust accumulated in the atmosphere during dry periods and were scavenged by rain. The rainwater in the study area is characterized by low salinity and neutral pH. The major ions found in rainwater followed the order of HCO3?>?Cl??>?SO4 2? and Ca2+?>?Na+ > Mg2+ > NH4 + > K+. Trace metals were identified to be of anthropogenic origin resulting from cement and phosphate mining activities located within the investigated area and from heating activities during the cold period of the year (January to April). The wet precipitation chemistry was analyzed using factor component analysis for possible sources of the measured species. Factor analysis (principal component analysis) was used to assess the relationships between the concentrations of the studied ions and their sources. Factor 1 represents the contribution of ions from local anthropogenic activities, factor 2 represents the contribution of ions from natural sources, and factor 3 suggests biomass burning and anthropogenic source. Overall, the results revealed that rainwater chemistry is strongly influenced by local anthropogenic sources rather than natural and marine sources, which is in a good agreement with the results obtained by other studies conducted in similar sites around the world.  相似文献   
982.
Environmental Science and Pollution Research - Dams are studied not only for potential advantages but also for possible environmental repercussions. The objective of this case study is to see the...  相似文献   
983.
Environmental Science and Pollution Research - Determining the water contamination of a river that threatens the dependent ecological community is a pillar for sustainable management. For this...  相似文献   
984.
Environmental Science and Pollution Research - For an economy to excel in growth, there is usually a trade-off between financial development and environment deterioration. For a country like...  相似文献   
985.
Environmental Science and Pollution Research - Organopesticides (OPs) are a group of various synthetic chemicals prevalently used in agriculture and homestead plantations. OPs were originally...  相似文献   
986.
Environmental Geochemistry and Health - Unfortunately, in the original publication of the article, Prof. Yang Sik Ok’s affiliation was incorrectly published. The author’s affiliation is...  相似文献   
987.

Polycyclic aromatic hydrocarbons as byproducts of carbon-based fuel combustion are an important group of pollutants with wide distribution in the environment. Polycyclic aromatic hydrocarbons are known as toxic compounds for almost all organisms. Different plant species can uptake polycyclic aromatic hydrocarbons by roots and translocate them to various aerial parts. The aim of this study is to investigate the uptake, translocation, and accumulation of pyrene and phenanthrene in maize under controlled conditions. Seeds were cultivated in perlite containing 25, 50, 75, and 100 ppm of phenanthrene and pyrene, and their concentrations in the roots and shoots of the plants were measured using high-performance liquid chromatography technique after 7, 14, and 21 days. The results revealed that phenanthrene naturally existed in maize and its concentration showed a time-dependent decrease in shoots and roots. In contrast, the concentration of pyrene was increased in the roots and reduced in the shoots. Although pyrene had higher uptake than phenanthrene in roots of maize, the translocation factor value for pyrene was lower than for phenanthrene. According to these findings, phenanthrene could be metabolized in maize in the shoot and root tissues, but pyrene had more tendency to be accumulated in roots.

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988.

This study investigated the characteristics of iron corrosion scales in pipes at tube well, overhead tank, and consumers’ end in older untreated water distribution system in Peshawar city, Pakistan. Effect of water quality conditions on corrosion scales and that of scales on drinking water quality in such systems was also assessed by undertaking a comparison with new piped distribution systems. The scales were analyzed for chemical composition and morphology using X-ray diffraction (XRD), inductively coupled plasma (ICP), and a scanning electron microscope (SEM), while water quality was examined for physicochemical and biological characteristics. The main crystalline phases of corrosion scales were goethite, magnetite, siderite, and quartz. From tube well to consumers’ end, goethite increased from 36 up to 48%, quartz declined from 22 to 15%, while magnetite fluctuated and siderite disappeared. Elemental composition of scales showed the deposition of Zn, Al, Mn, Cr, Pb, Cu, As, and Cd with Zn (13.9 g/kg) and Al (3.6 g/kg) in highest proportion. The SEM analysis illustrated the presence of microbial communities indicating the formation of biofilms in the corrosion scales. The significant difference (P <?0.05) in levels of dissolved oxygen (DO), Cl?, SiO44?, electrical conductivity (EC), SO42?, NO3?, alkalinity, hardness, and trace metals between old (DS-O) and new piped systems indicated their role in corrosion scale formation/destabilization and the effect of scale dissolution on water quality. In DS-O, EC, Cu, and Mn were significantly higher (P?<?0.05), whereas turbidity, EC, DO, and SiO44? significantly increased from source to consumers’ end implying a higher dissolution of scales and lowered corrosion rates in DS-O to utilize SiO44? and DO for iron oxidation.

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989.

Date palm waste–derived biochar (DBC) was produced through pyrolysis (600 °C) and modified with zeolite (Z-DBC), silica (S-DBC), or nano-zerovalent iron (nZVI-DBC) to design efficient sorbents. The pristine and engineered biochars were characterized by SEM, XRD, BET, TGA, CHNS-O, and FTIR to investigate the surface, structural, and mineralogical composition. The nZVI-DBC exhibited lowest pH (6.15) and highest surface area (220.92 m2 g−1), carbon (80.55%), nitrogen (3.78%), and hydrogen (11.09%) contents compared with other biochars. Isotherm sorption data for chlortetracycline (CTC) removal from aqueous solutions was described well by Langmuir and Redlich–Peterson isotherms showing the highest fitness (R2 values in the range of 0.88–0.98 and 0.88–0.99, respectively). Langmuir predicted maximum CTC adsorption capacity was in order of nZVI-DBC (89.05 mg g−1) > S-DBC (45.57 mg g−1) > Z-DBC (30.42 mg g−1) > DBC (28.19 mg g−1). Kinetics adsorption data was best described by power function model (R2 = 0.93–0.99), followed by interaparticle diffusion (R2 = 0.85–0.96) model. The nZVI-DBC performed outclass by removing 98% of CTC, followed by S-DBC (68%), Z-DBC (35%), and DBC (36%). Chemisorption, H-bonding, and interaparticle diffusion were the operating mechanisms for CTC adsorption onto DBC, S-DBC, and Z-DBC, while π-π electron donor–accepter interactions and redox reactions augmented these mechanisms for highest CTC adsorption onto nZVI-DBC. Therefore, nZVI-DBC may serve as an efficient green technology for the removal of CTC from aqueous solutions and to reduce surface date palm waste pollution.

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990.
Environmental Chemistry Letters - Water pollution by human activities is major issue. In particular, toxic metals are of particular concern, thus calling for advanced methods to remove metals from...  相似文献   
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